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Bio-based polyurethane for road engineering applications:A comprehensive review
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作者 Qingxu Li Zengping Zhang +3 位作者 Zhongbao Shi Yekun Zhang Xiaoyi Ban Hao Liu 《Journal of Road Engineering》 2025年第4期513-530,共18页
With the escalating global emphasis on environmental conservation and sustainable development,enhancing the service quality and durability of road surfaces and facilitating the green development of highways have comma... With the escalating global emphasis on environmental conservation and sustainable development,enhancing the service quality and durability of road surfaces and facilitating the green development of highways have commanded considerable attention.Bio-based polyurethane,on account of its remarkable physical and chemical properties,green,sustainable and renewable capacity,as well as its structural design capabilities,has drawn widespread attention and numerous studies have been carried out.It has gradually started to substitute traditional petroleum-based polyurethane materials in road engineering.Nevertheless,the application of bio-based polyurethane materials in road engineering remains in the exploratory phase.To stimulate the application research of bio-based polyurethane materials in road engineering and offer additional research directions,this paper reviews the research advancements of bio-based polyurethane materials and their applications in road engineering.The fundamental classification of bio-based polyurethane is introduced.The characteristics and challenges associated with various preparation methods for bio-based polyurethane are described.The influence of bio-based polyurethane on road engineering materials are analyzed.The evaluation indicators of bio-based polyurethane within the life cycle of road engineering are investigated.Finally,the development tendency towards in road engineering applications are forecasted.This paper provides a reference for the study of bio-based polyurethane materials in road engineering applications. 展开更多
关键词 bio-based materials POLYURETHANE Life cycle assessment Environmentally friendly
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4-Bromophthalic Anhydride-based Polyesters as a Versatile Modified Platform
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作者 Ming-Xin Niu Chen-Yang Hu +1 位作者 Xuan Pang Xue-Si Chen 《Chinese Journal of Polymer Science》 2025年第6期958-963,I0008,共7页
Chemical modification of polymers represents a pivotal method for achieving functionalized polymer materials.However,due to the lack of post-functional handle,the chemical modification of polyester materials remains a... Chemical modification of polymers represents a pivotal method for achieving functionalized polymer materials.However,due to the lack of post-functional handle,the chemical modification of polyester materials remains a significant challenge.Ring-opening copolymerization of cyclic anhydride and epoxides is a powerful approach to synthesize polyesters.In this work,we for the first time demonstrate the functionalizability of polyesters synthesized with brominated anhydride monomers.The post-functionalization is amenable to a wide variety of reactive groups and reactions with high yields.With multiple well-established functionalization pathways of brominated polyester materials and optimized the conditions for the modification reactions,a series of functionalized polyester materials can be obtained with high yields,providing new insights for the research about functionalization of polymers. 展开更多
关键词 polyesters Bromophthalic anhydride FUNCTIONALIZATION Modification
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Research Progress on Bio-Based Biodegradable Barrier Materials
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作者 Kezheng Gao Shuaifei Li +1 位作者 Qingyuan Niu Xiaojing Zhang 《Journal of Renewable Materials》 2025年第12期2309-2353,共45页
The current global shortage of oil resources and the pollution problems caused by traditional barrier materials urgently require the search for new substitutes.Biodegradable bio-based barrier materials possess the cha... The current global shortage of oil resources and the pollution problems caused by traditional barrier materials urgently require the search for new substitutes.Biodegradable bio-based barrier materials possess the characteristics of being renewable,environmentally friendly,and having excellent barrier properties.They have become an important choice in fields such as food packaging,agricultural film covering,and medical protection.This review systematically analyzes the design and research of this type of material,classifying biobased and biodegradable barrier materials based on the sources of raw materials and synthesis pathways.It also provides a detailed introduction to the latest research progress of biobased and biodegradable barrier materials,discussing the synthesis methods and improvement measures of their barrier properties.Subsequently,it analyzes the related technologies for enhancing the barrier properties of biobased and biodegradable barrier materials,and finally looks forward to the directions that future research should focus on,promoting the transition of biobased and biodegradable barrier materials from the laboratory to industrial applications. 展开更多
关键词 bio-based materials BIODEGRADABLE barrier material barrier performance enhance barrier measures
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Installation of Multiple Chiral Centers in Aliphatic Polyesters Backbone Enables Unexpected Crystallinity via Asymmetric Catalytic Copolymerization
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作者 Zheng-Fei Liu Bai-Hao Ren +4 位作者 Yi-Shu Fu Jun Yang Yong-Qiang Teng Ye Liu Xiao-Bing Lu 《Chinese Journal of Polymer Science》 2025年第6期946-951,I0008,共7页
The asymmetric alternating copolymerization of meso-epoxide and cyclic anhydrides provides an efficient access to enantiopure polyesters.Contrary to the extensive investigation of the stereochemistry resulting from ep... The asymmetric alternating copolymerization of meso-epoxide and cyclic anhydrides provides an efficient access to enantiopure polyesters.Contrary to the extensive investigation of the stereochemistry resulting from epoxide building block,the chirality from anhydride and the configurational match with epoxide remain elusive.Herein,we discover that the bimetallic chromium catalysts have led to an obvious enhancement in terms of reactivity and enantioselectivity for the asymmetric copolymerization of meso-epoxide with various non-symmetric chiral anhydrides.Up to 97%ee was obtained during the asymmetric copolymerization of cyclohexene oxide(CHO)with(R)-methylsuccinic anhydride(R-MSA),and three-or four-carbon chiral centers were simultaneously installed in the aliphatic polyester backbone.In particular,the different combinations of stereochemistry in epoxide and anhydride building blocks considerably affect the thermal properties and crystalline behaviors of the resulting polyesters.This study uncovers an interesting method for regulating polymer crystallinity via matching the chirality of different monomers. 展开更多
关键词 CHIRALITY Bimetallic catalyst Asymmetric copolymerization Aliphatic polyester
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Bio-based Epoxy Composites Demonstrating High Temperature Breakdown Strength and Thermal Conductivity for High Voltage Insulation
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作者 Ke-Rong Yang Jin-Yue Dai +2 位作者 Shuai-Peng Wang Wei-Wei Zhao Xiao-Qing Liu 《Chinese Journal of Polymer Science》 2025年第1期40-52,I0006,共14页
The demand for energy-efficient and environmental-friendly power grid construction has made the exploitation of bio-based electrical epoxy resins with excellent properties increasingly important.This work developed th... The demand for energy-efficient and environmental-friendly power grid construction has made the exploitation of bio-based electrical epoxy resins with excellent properties increasingly important.This work developed the bio-based electrotechnical epoxy resins based on magnolol.High-performance epoxy resin(DGEMT)with a double crosslinked points and its composites(Al_(2)O_(3)/DGEMT)were obtained taking advantages of the two bifunctional groups(allyl and phenolic hydroxyl groups)of magnolol.Benefitting from the distinctive structure of DGEMT,the Al_(2)O_(3)/DGEMT composites exhibited the advantages of intrinsically high thermal conductivity,high insulation,and low dielectric loss.The AC breakdown strength and thermal conductivity of Al_(2)O_(3)/DGEMT composites were 35.5 kV/mm and 1.19 W·m-1·K-1,respectively,which were 15.6%and 52.6%higher than those of petroleum-based composites(Al_(2)O_(3)/DGEBA).And its dielectric loss tanδ=0.0046 was 20.7%lower than that of Al_(2)O_(3)/DGEBA.Furthermore,the mechanical,thermal and processing properties of Al_(2)O_(3)/DGEMT are fully comparable to those of Al_(2)O_(3)/DGEBA.This work confirms the feasibility of manufacturing environmentally friendly power equipment using bio-based epoxy resins,which has excellent engineering applications. 展开更多
关键词 bio-based epoxy composites MAGNOLOL Breakdown strength Thermal conductivity Dielectric loss
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Development of Oilfield Blockage Relief and Injection System Based on Bio-Based Surfactants
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作者 Wang Fei Chen Zhaoxian +2 位作者 Liu Gang Zhang Huili Hu Meijuan 《China Detergent & Cosmetics》 2025年第3期40-46,共7页
By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permea... By investigating the performance characteristics of the bio-based surfactant 8901A,a composite decontamination and injection system was developed using 8901A as the primary agent,tailored for application in low-permeability and heavy oil reservoirs under varying temperature conditions.The results demonstrate that this system effectively reduces oil–water interfacial tension,achieving an ultra-low interfacial tension state.The static oil washing efficiency of oil sands exceeds 85%,the average pressure reduction rate reaches 21.55%,and the oil recovery rate improves by 13.54%.These enhancements significantly increase the system’s ability to dissolve oilbased blockages,thereby lowering water injection pressure caused by organic fouling,increasing the injection volume of injection wells,and ultimately improving oil recovery efficiency. 展开更多
关键词 bio-based surfactants oil extraction technology pressure reduction and blockage relief
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Biobased Polyesters Derived from 2-Methoxyhydroquinone:Impact of Cyclic and Alkyl Chain Segments on Their Thermomechanical Properties,Biodegradability,and Ecotoxicity
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作者 Hao-Ming Xu Zheng-Zai Cheng +2 位作者 Zi-Ting Zhou Lesly Dasilva Wandji Djouonkep Mario Gauthier 《Chinese Journal of Polymer Science》 2025年第8期1320-1332,共13页
To enhance the properties of bio-based polyesters,enabling them to more closely mimic the characteristics of terephthalate-based materials,a series of aliphatic-aromatic copolyesters(P_(1)–P_(4))were synthesized via ... To enhance the properties of bio-based polyesters,enabling them to more closely mimic the characteristics of terephthalate-based materials,a series of aliphatic-aromatic copolyesters(P_(1)–P_(4))were synthesized via melt polycondensation.Diester monomers M and N were synthesized via the Williamson reaction,using lignin-derived 2-methoxyhydroquinone,methyl 4-chloromethylbenzoate,and methyl chloroacetate as starting materials.Hydroquinone bis(2-hydroxyethyl)ether(HQEE)and 1,4-cyclohexanedimethanol(CHDM)were employed as cyclic segments,while 1,4-butanediol(BDO)and 1,6-hexanediol(HDO)served as alkyl segments within the copolymer structures.The novel copolyesters exhibited molecular weights(Mw)in the range of 5.25×10^(4)–5.87×10^(4) g/mol,with polydispersity indices spanning from 2.50–2.66.Evaluation of the structural and thermomechanical properties indicated that the inclusion of alkyl segments induced a reduction in both crystallinity and molecular weight,while significantly improving the flexibility,whereas cyclic segments enhanced the processability of the copolyesters.Copolyesters P_(1) and P_(2),due to the presence of rigid segments(HQEE and CHDM),displayed relatively high glass transition temperatures(Tg>80℃)and melting temperatures(Tm>170℃).Notably,P_(2),incorporating CHDM,exhibited superior elongation properties(272%),attributed to the enhanced chain mobility resulting from its trans-conformation,while P_(1) was found to be likely brittle owing to excessive chain stiffness.Biodegradability assessment using earthworms as bioindicators revealed that the copolyesters demonstrated moderate degradation profiles,with P_(2) exhibiting a degradation rate of 4.82%,followed by P_(4) at 4.07%,P_(3) at 3.65%,and P_(1) at 3.17%.The higher degradation rate of P_(2) was attributed to its relatively larger d-spacing and lower toxicity,which facilitated enzymatic hydrolytic attack by microorganisms.These findings highlight the significance of optimizing the structural chain segments within aliphatic-aromatic copolyesters.By doing so,it is possible to significantly enhance their properties and performance,offering viable bio-based alternatives to petroleum-based polyesters such as polyethylene terephthalate(PET). 展开更多
关键词 2-Methoxyhydroquinone Aliphatic-aromatic polyesters Cyclic and alkyl chain segments BIODEGRADABILITY
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Comprehensive review of aging phenomena in conventional and bio-based asphalt binders:Challenges and future directions
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作者 Farhad Sakanlou Chiara Riccardi Massimo Losa 《Journal of Road Engineering》 2025年第4期481-512,共32页
Aging plays a critical role in determining the durability and long-term performance of asphalt pavements,as it is influenced by both external factors(e.g.,temperature,ultraviolet(UV)radiation,moisture,oxidative gases)... Aging plays a critical role in determining the durability and long-term performance of asphalt pavements,as it is influenced by both external factors(e.g.,temperature,ultraviolet(UV)radiation,moisture,oxidative gases)and internal factors such as binder composition.Although laboratory simulations of aging are well established for conventional bituminous binders,limited attention has been paid to replicating and evaluating aging processes in bio-based binders.This review provides a comprehensive analysis of current laboratory techniques for simulating and assessing binder aging,with a focus on two key areas:aging simulation protocols and evaluation methodologies.The analysis shows that although several efforts have been made to incorporate external aging factors into lab simulations,significant challenges persist,especially in the case of bio-based binders,which are characterized by a high variability in composition and limited understanding of their aging behavior.Current evaluation approaches also exhibit limitations.Improvements are needed in the molecular-level analysis of oxidation(e.g.,through more representative oxidation modelsin molecular dynamicssimulations),in the separation and quantification of binder constituents,and in the application of advanced techniques such as fluorescence microscopy to better characterize polymer dispersion.To enhance the reliability of laboratory simulations,future research should aim to improve the correlation between laboratory and field aging,define robust aging indexes,and refine characterization methods.These advancements are particularly critical for bio-based binders,whose performance is highly sensitive to aging and for which standard test protocols are still underdeveloped.A deeper understanding of aging mechanisms in both polymer-modified and biobased binders,along with improved analytical tools for assessing oxidative degradation and morphological changes,will be essential to support the development of sustainable,high-performance paving materials. 展开更多
关键词 Binder aging bio-based binder aging UV aging Moisture aging Molecular dynamics simulation Aging index
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Influence of Millet Husks on the Physical, Mechanical and Thermal Performance of a Lightweight Bio-Based Concrete
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作者 Soubérou Gbèdossou Saloufou Valéry KouandétéDoko +2 位作者 Edem Chabi Emmanuel Olodo Mohamed Gibigaye 《材料科学与工程(中英文A版)》 2025年第1期19-31,共13页
In the context of transitioning toward more sustainable construction materials,this study explores the impact of incorporating millet husks as an alternative to sand on the physical,mechanical,and thermal performance ... In the context of transitioning toward more sustainable construction materials,this study explores the impact of incorporating millet husks as an alternative to sand on the physical,mechanical,and thermal performance of lightweight concrete.Through a mixture design approach,five formulations were selected and thoroughly characterized.The analysis of iso-response curves enabled an in-depth assessment of the cross-effects between formulation parameters and their interactions on the final properties of the material.The results show that integrating millet husks leads to a significant reduction in density,reaching up to 21%,while maintaining notable mechanical performance.A balanced formulation of sand and fibers achieved a maximum compressive strength of 12.11 MPa,demonstrating that,under specific conditions,plant fibers actively contribute to the structural integrity of the composite.In tensile strength,the positive influence of fibers is even more pronounced,with a maximum resistance of 8.62 MPa,highlighting their role in enhancing material cohesion.From a thermal perspective,millet husks reduce both thermal conductivity and effusivity,thereby limiting heat transfer and accumulation within the composite.Iso-response curve analysis reveals that these effects are directly linked to the proportions of the constituents and that achieving an optimal balance between sand,fibers,and cement is key to maximizing performance.These findings demonstrate that the adopted approach allows moving beyond conventional substitution methods by identifying optimal configurations for the design of lightweight bio-based concretes that are both strong and insulating,thereby confirming the potential of millet husks in developing lightweight concretes suitable for sustainable construction applications. 展开更多
关键词 Lightweight bio-based materials plant fibers mixture design iso-response analysis formulation optimization mineral aggregate substitution.
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Recent progress of heterocycle ring-opening(co)polymerization for the synthesis of sequence-controlled block polyesters and polycarbonates
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作者 Hongyu Zhao Chenyang Hu +1 位作者 Xuan Pang Xuesi Chen 《Smart Molecules》 2025年第4期1-19,共19页
Aliphatic polyesters and polycarbonates are among the promising sustainable polymers,which exhibit unique degradability and chain-chain interactions owing to their heterofunctionality.However,monocomponent aliphatic p... Aliphatic polyesters and polycarbonates are among the promising sustainable polymers,which exhibit unique degradability and chain-chain interactions owing to their heterofunctionality.However,monocomponent aliphatic polyesters and polycarbonates usually suffer from inferior properties and functionalities.By contrast,precisely modulated block copolymers composed of polyesters and polycarbonates give rise to sustainable materials with tailored performance.An efficient approach to synthesize the block copolymers is the ring-opening(co)polymerization of the heterocycle monomers.Herein,this review presents the heterocycle monomer ring-opening(co)polymerization for the formation of sequence-controlled block polyesters and polycarbonates.Available synthetic strategies,different monomers,monomer combinations and the catalyst systems for the formation of different block polyesters and polycarbonates are summarized. 展开更多
关键词 aliphatic polycarbonates aliphatic polyesters block copolymers heterocycle monomers ring-opening(co)polymerization
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Effect of Heat Treatment on Molecular Mass and Thermal Properties of Thermotropic Liquid Crystal Polyesters
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作者 DONG Shihang CHEN Yufeng +4 位作者 WAN Hai LIANG Yuan HUANG Shuohan WANG Yanping XIA Yumin 《Journal of Donghua University(English Edition)》 2025年第2期124-135,共12页
The thermotropic liquid crystal polyester(TLCP)fiber is an increasingly important strategic high-performance fiber.In this paper,the TLCP was prepared by two-step melt polymerization using 4-hydroxybenzoic acid(HBA)an... The thermotropic liquid crystal polyester(TLCP)fiber is an increasingly important strategic high-performance fiber.In this paper,the TLCP was prepared by two-step melt polymerization using 4-hydroxybenzoic acid(HBA)and 6-hydroxy-2-naphthoic acid(HNA)as comonomers at a molar ratio of 7∶3.The structure of TLCP was confirmed by the Fourier transform infrared(FTIR)spectrometer and nuclear magnetic resonance(NMR)spectrometer.The thermal and rheological properties of TLCP before and after heat treatment were analyzed systematically by the differential scanning calorimeter(DSC),dynamic mechanical analyzer(DMA)and high-temperature rotational rheometer.The results revealed that the melting temperature,glass transition temperature and melt viscosity of the TLCP increased significantly after heat treatment.It indicates that the crystallization of the TLCP is perfect,and solid-phase condensation occurs during heat treatment,which increases its molecular mass.In conclusion,heat treatment at a temperature below but close to the melting temperature can effectively regulate the structure and properties of the TLCP,and the results of this study can provide a reference for the high strengthening of TLCP fibers. 展开更多
关键词 thermotropic liquid crystal polyester(TLCP) heat treatment VISCOSITY thermal property
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Switching electronic effects of UiO-67-Pd using fluorinated ligands for catalytic oxidative arylation of bio-based furfuryl alcohol
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作者 Dongwen Guo Guohui Zeng +1 位作者 Jinxing Long Biaolin Yin 《Chinese Journal of Catalysis》 2025年第2期230-240,共11页
An efficient and novel approach is proposed for oxidative arylation of bio-based furfuryl alcohol(FA)to aryl furans(AFs),a versatile monomer of photoelectric materials,in the presence of UiO-67-Pd(F)with phenanthrolin... An efficient and novel approach is proposed for oxidative arylation of bio-based furfuryl alcohol(FA)to aryl furans(AFs),a versatile monomer of photoelectric materials,in the presence of UiO-67-Pd(F)with phenanthroline/bipyridine,and poly-F substituted phenyl ligands as the mixture linkers.The results of control experiments and theoretical calculations reveal that the–F on the phenyl linkers efficiently tunes the electron-deficient nature of Pd through the Zr_(6) clusters bridges,which favors the adsorption and activation of the furan ring.Furthermore,the conjugation of different nitrogen-containing ligands facilitates Pd coordination for the Heck-type insertion and subsequent electrophilic palladation,respectively.As a result,the oxidative arylation of FA derivatives is substantially enhanced because of these electronic and steric synergistic effects.Under the optimized conditions,72.2%FA conversion and 74.8%mono aryl furan(MAF)selectivity are shown in the Heck-type insertion.Meanwhile,85.3%of MAF is converted,affording 74.8%selectivity of final product(AFs)in the subsequent electrophilic palladation reaction.This process efficiency is remarkably higher than that with homogeneous catalysts.In addition,furan-benzene polymer obtained from the halogen-free synthesis catalyzed by UiO-67-Pd(F)show significantly better properties than that from conventional Suzuki coupling method.Therefore,the present work provides a new insight for useful AFs synthesis by oxidative arylation of bio-furan via rational tunning the metal center micro-environment of heterogeneous catalyst. 展开更多
关键词 bio-based furan Catalytic oxidative arylation UiO-67-Pd(F)catalyst Ligand regulation Charge separation
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High-performance freshwater-hydroelectricity co-generation by porous carbon through waste polyester-derived MOF-assisted carbonization
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作者 Yan She Guixin Hu +7 位作者 Xueying Wen Huiyue Wang Ming Yang Lingling Feng Zhikun Dai Qianyu Wei Ran Niu Jiang Gong 《Science China Materials》 2026年第3期1508-1517,共10页
The integration of interfacial photothermal conversion and hydrovoltaic effect into bifunctional evaporators has emerged as a hopeful approach to address water and energy scarcities.However,developing low-cost bifunct... The integration of interfacial photothermal conversion and hydrovoltaic effect into bifunctional evaporators has emerged as a hopeful approach to address water and energy scarcities.However,developing low-cost bifunctional evaporators and elucidating the freshwater-electricity co-generation mechanism remain challenging.In this work,we prepare porous carbon from waste polyester through a metalorganic framework(MOF)-assisted carbonization strategy and subsequently fabricate a bifunctional evaporator for freshwater-hydroelectricity co-generation.The porous carbon contains rich oxygen-containing groups and shows hierarchical micro-and mesopores with a high specific surface area of 904 m^(2)g^(-1).The porous carbon-based evaporator shows broadband and high light absorption,localized thermal management,good hydrophilicity,and high flexibility.Benefiting from these merits,it achieves high-performance freshwater and hydroelectricity co-generation,with the opencircuit voltage of 250 mV,the short-circuit current of 14μA,and the evaporation rate of 2.34 kg m^(-2)h^(-1).Hence,it is ranked among the most efficient freshwater-hydroelectricity co-generator.Additionally,the weakened hydrogen-bonding network reduces water evaporation enthalpy to 1.7 kJ g^(-1).Mechanistic investigations reveal that selective Na+interaction induces differential ion migration rate to generate streaming potential,as evidenced by molecular dynamics simulations.Meanwhile,the photothermal effect enhances voltage output by promoting interfacial ion concentration gradients.During the outdoor freshwater-electricity co-generation,it shows the voltage output of 250 mV and freshwater production of 2.34 kg m-2.This work not only puts forward a new platform to fabricate advanced evaporators from low-cost waste plastics but also unravels the freshwater-electricity co-generation mechanism,offering scalable strategies to tackle freshwater and energy crises. 展开更多
关键词 waste polyester metal-organic framework porous carbon interfacial solar steam generation hydrovoltaic electricity generation
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Unconfined compressive strength and small-strain shear modulus of soft marine clay improved by ordinary Portland cement and polyester fibers with modeling by Michaelis-Menten kinetics
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作者 Keeratikan Piriyakul Aruz Petcherdchoo +1 位作者 Koonnamas Punthutaecha Tanakorn Phoo-ngernkham 《Journal of Road Engineering》 2026年第1期134-147,共14页
This study proposes to use the unconfined compressive strength(UCS)and the bender element(BE)tests for determining the strength and the initial small-strain shear modulus of Bangkok soft marine clay improved by cement... This study proposes to use the unconfined compressive strength(UCS)and the bender element(BE)tests for determining the strength and the initial small-strain shear modulus of Bangkok soft marine clay improved by cement and polyester fibers.This study varies the content of admixed cement(1%–20%)and polyester fibers(0–20%),including the curing time(3–28 d)for preparing 360 samples.Moreover,this study uses the Michaelis-Menten kinetics concept to model cement hydration saturation.From the study,it is concluded as follows.The modelled results reveals that at least 10%cement and 1%polyester fiber are recommended to attain the 28-d UCS standards(294 kPa)for highway subgrade materials in Thailand.This also fulfils sustainable construction due to reducing normal-use cement from 20%to 10%.Unfortunately,the addition of polyester fibers into the Bangkok clay with at least 5%cement reduces shear modulus by 1.12–1.32 times.The Abram's relationship between shear modulus and the mixing-water-to-cement ratio is found time-dependent.From the composite theory,the BE detects the polyester fiber zone as a defect in the Bangkok clay(matrix)with 5%–20%cement.So,the 28-d shear modulus in the polyester fiber zone is negative(up to0.034 MPa for 20%fiber),similar to softening phenomenon in concrete cracking(negative stiffness).For the 28-d shear modulus of fiber zone,the optimum cement content is around 2%for the positive influences of polyester fibers.Experimentally,the timedependent normalized UCS for 10%and 20%cement is compatible with other studies,and its development rate increases with the cement content as 0.3017,0.3172 and 0.3204 for 5%,10%and 20%cement,respectively.The 28-d relationship between shear modulus and UCS shows that low-cement soft clay requires high polyester fiber content(5%–20%)to activate UCS improvement.However,the soft clay with enough cement(20%)causes the uniformly distributed UCS improvement. 展开更多
关键词 Bangkok soft marine clay Unconfined compressive strength Small-strain shear modulus Bender elements polyester fibers Michaelis-Menten kinetics
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SYNTHESIS AND CHARAOTERIZATION OF NOVEL THERMOTROPIO LIQUID ORYSTALLINE POLYESTERS BEARING NONLINEAR OPTICAL AZOBENZENE SIDE GROUP
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作者 张会旗 张莹 +2 位作者 甘湘萍 阴航明 孙经武 《Transactions of Tianjin University》 EI CAS 1999年第1期93-97,共5页
A series of novel thermotropic liquid crystalline polyesters bearing nonlinear optical azobenzene side group were synthesized by high temperature solution polycondensation and their structures,thermal stability, phas... A series of novel thermotropic liquid crystalline polyesters bearing nonlinear optical azobenzene side group were synthesized by high temperature solution polycondensation and their structures,thermal stability, phase transition behavior and crystallinity were characterized by IR,elemental analysis, TG-DTA, polarizing optical microscope (POM) equipped with a hot stage and X-ray diffraction techniques. The results demonstrate that all the synthesized polyesters exhibit nematic liquid crystalline phases and show relatively high glass transition temperatures and good thermal stability. 展开更多
关键词 AZOBENZENE polyestER thermotropic liquid crystalline polymer nematic phase nonlinear optical material
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Robust and Reprocessable Biorenewable Polyester Nanocomposites In Situ Catalyzed and Reinforced by Dendritic MXene@CNT Heterostructure
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作者 Hao Wang Jiheng Ding +3 位作者 Hongran Zhao Qinchao Chu Jin Zhu Jinggang Wang 《Nano-Micro Letters》 2025年第7期206-222,共17页
Renewable 2,5-furandicarboxylic acid-based polyesters are one of the most promising materials for achieving plastic replacement in the age of energy and environmental crisis.However,their properties still cannot compe... Renewable 2,5-furandicarboxylic acid-based polyesters are one of the most promising materials for achieving plastic replacement in the age of energy and environmental crisis.However,their properties still cannot compete with those of petrochemical-based plastics,owing to insufficient molecular and/or microstructure designs.Herein,we utilize the Ti_(3)C_(2)T_(x)-based MXene nanosheets for decorating carbon nanotube(CNT)and obtaining the structurally stable and highly dispersed dendritic heterostructured MXene@CNT,that can act as multi-roles,i.e.,polycondensation catalyst,crystal nucleator,and interface enhancer of polyester.The biobased MXene@CNT/polybutylene furandicarboxylate(PBF)(denoted as MCP)nanocomposites are synthesized by the strategy of“in situ catalytic polymerization and hot-pressing”.Benefiting from the multi-scale interactions(i.e.,covalent bonds,hydrogen bonds,and physical interlocks)in hybrid structure,the MCP presents exceptional mechanical strength(≈101 MPa),stiffness(≈3.1 GPa),toughness(≈130 MJ m^(-3)),and barrier properties(e.g.,O_(2)0.0187 barrer,CO_(2)0.0264 barrer,and H2O 1.57×10^(-14) g cm cm^(-2) s Pa)that are higher than most reported bio-based materials and engineering plastics.Moreover,it also displays satisfactory multifunctionality with high reprocessability(90%strength retention after 5 recycling),UV resistance(blocking 85%UVA rays),and solvent-resistant properties.As a state-of-art high-performance and multifunctional material,the novel bio-based MCP nanocomposite offers a more sustainable alternative to petrochemical-based plastics in packaging and engineering material fields.More importantly,our catalysis-interfacial strengthening integration strategy opens a door for designing and constructing high-performance bio-based polyester materials in future. 展开更多
关键词 bio-based polyesters nanocomposites Dendritic hetero-structured MXene@CNT Catalysis-interfacial strengthening integration High strength and toughness Reprocessability and multifunctionality
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Bio-Based Hyperbranched Toughener From Tannic Acid and Its Enhanced Solvent-Free Epoxy Resin with High Performance 被引量:7
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作者 Jie Xu Jiayao Yang +5 位作者 Hengxu Wang Peng Lin Xiaohuan Liu Jinjie Zhang Shenyuan Fu Yuxun Tang 《Journal of Renewable Materials》 SCIE 2019年第12期1333-1346,共14页
It is essential to design economic and efficient tougheners to prepare high-performance epoxy resin;however,this has remained a huge challenge.Herein,an eco-friendly,low-cost,and facile-fabricated bio-based hyperbranc... It is essential to design economic and efficient tougheners to prepare high-performance epoxy resin;however,this has remained a huge challenge.Herein,an eco-friendly,low-cost,and facile-fabricated bio-based hyperbranched toughener,carboxylic acid-functionalized tannic acid(CATA),was successfully prepared and applicated to the preparation of solvent-free epoxy resins.The mechanical performance,morphology,structural characterization,and thermal characterization of toughened epoxy resin system were studied.The toughened epoxy resin system with only 1.0wt%CATA reached the highest impact strength,111%higher than the neat epoxy resin system.Notably,the tensile strength and elongation at break of toughened epoxy resin systems increased moderately with increasing CATA loading.Nonphase-separated hybrids with significant toughening effect were obtained.Additionally,the thermal stabilities of toughened epoxy resin systems decreased with increasing CATA loading.This study provides an eco-friendly,cost-effective,and facile approach for the preparation of high-performance,solvent-free epoxy resins with potential for practical applications in sealing integrated circuits and electrical devices fields. 展开更多
关键词 Solvent-free epoxy resins bio-based toughener bio-based curing agent mechanical performance thermal properties
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Efficient synthesis of hydroxyl functioned polyesters from natural polyols and sebacic acid 被引量:5
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作者 Zhuo Yuan Ning Qing Shan Zhang Qin Pei Wu Yun Zheng Li Dong Xia Ma Jia Zhe Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第6期635-638,共4页
Amphiphilic hydroxyl functioned polyester(HFP) can be used as compatibilizers for blends of starch and resins.We developed a synthetic method for effective preparation of HFPs.Water was removed by high flow rate N_2... Amphiphilic hydroxyl functioned polyester(HFP) can be used as compatibilizers for blends of starch and resins.We developed a synthetic method for effective preparation of HFPs.Water was removed by high flow rate N_2 rather than high vacuum during polycondensation of sebacic acid with xylitol,sorbitol,or mannitol in the presence of dehydrative condensation catalyst and the product is with[η]of 27.2 mL/g,M_n of 1903,M_w of 167,693,T_g of -30.5℃,T_m of 44.0℃.Weight loss is 1.73%under 200℃. The integral distributions of molecular weight are 43.6 wt%and 63.8 wt%over 10,000 and 3000,respectively.The results indicated that higher molecular weight HFP was economically synthesized. 展开更多
关键词 Hydroxyl functioned polyester Poly(sorbitol sebacate) Dehydrative condensation catalyst Biodegradable plastics
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High Performance Bio-based Polyurethane Elastomers: Effect of Different Soft and Hard Segments 被引量:7
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作者 Bin Cui Qing-Yun Wu +2 位作者 顾林 Liang Shen 余海斌 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2016年第7期901-909,共9页
In this work, a series of high performance bio-based polyurethanes(bio-PUs) were synthesized from polylactide(PLA)-based diols, different diisocyanates(TDI, MDI, HDI, IPDI) and chain extender 1,4-butanediol, in ... In this work, a series of high performance bio-based polyurethanes(bio-PUs) were synthesized from polylactide(PLA)-based diols, different diisocyanates(TDI, MDI, HDI, IPDI) and chain extender 1,4-butanediol, in which different soft and hard segments are used to adjust their transition temperatures and mechanical properties. Poly(lactide-co-caprolactone)copolymer diols(co-PLAols) instead of PLA diols as the soft segment improved the thermal stability and mechanical properties of the synthesized bio-PUs. Among them, MDI-based bio-PUs have the highest T_g(43.8 °C), tensile strength(23.5 MPa) and modulus(380.8 MPa), while HDI-based bio-PUs have the lowest T_g(21.4 °C) and highest elongation at break(580%). Especially, the bio-PUs synthesized from co-PLAols and MDI demonstrate better mechanical properties,closed to petroleum-based commodities. Furthermore, the obtained bio-PUs display good shape memory properties at body temperature and cytocompatibility. Therefore, these bio-PUs are promising for applications in biomedical fields. 展开更多
关键词 Polylactide diols bio-based polyurethane Shape memory BIOCOMPATIBILITY
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Synthesis of Eugenol Bio-based Reactive Epoxy Diluent and Study on the Curing Kinetics and Properties of the Epoxy Resin System 被引量:5
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作者 Bin Chen Feng Wang +3 位作者 Jing-Yu Li Jia-Lu Zhang Yan Zhang Hai-Chao Zhao 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2019年第5期500-508,共9页
In this study, monoglycidyl silyl etherated eugenol(GSE) was synthesized as reactive epoxy diluent, and the chemical structure of GSE, intermediates, and products were characterized by Fourier transform infrared spect... In this study, monoglycidyl silyl etherated eugenol(GSE) was synthesized as reactive epoxy diluent, and the chemical structure of GSE, intermediates, and products were characterized by Fourier transform infrared spectroscopy(FTIR) and nuclear magnetic resonance(~1 H-NMR). GSE existed as a potential bio-based reactive diluent for petroleum-based epoxy resin. The curing kinetics of EP/HHPA/GSE system was studied by non-isothermal DSC method. The kinetics parameters were calculated by using the Kissinger model, Crane model, Ozawa model, and β-T(temperature-heating rate) extrapolation, respectively. In addition, the effects of GSE on the thermo-mechanical properties and thermal stability of EP/HHPA/GSE systems were studied, indicating that GSE can effectively improve the toughness and thermal decomposition temperature of the epoxy system. 展开更多
关键词 bio-based EPOXY REACTIVE DILUENT EUGENOL CURING kinetics
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